1. Technical Field
This invention relates generally to a method for mounting a liquid crystal display panel in a mobile telecommunication instrument, and more particularly to such a method that is directed to facilitating automated assembly of a liquid crystal display panel in a mobile telecommunication instrument.
2. Background Art
It is desirable, in many mobile telecommunication instruments, such as cellular. telephones and similar devices, to have a liquid crystal display (LCD) panel which displays important data necessary to the operation of the instrument. A basic problem in assembling an LCD panel, in a mobile telephone instrument is the need to use additional mechanical components to secure the LCD panel in its desired position.
The additional components and the increased number of assembly operations required heretofore increases the overall cost of the instrument. For example, European Patent Office publication EP0735404A1, published Oct. 2, 1996 for Liquid Crystal Display, Its Mounting Structure, And Electronic Device discloses a horizontally mounted LCD panel. In this arrangement, additional components are needed to fixedly mount the panel in the instrument. The disclosed mounting arrangement requires an attachment fixture having feet that protrude through holes in a printed circuit board, which during assembly are bent, thereby forcedly pressing the LCD and a subjacently disposed light guide together, thereby fixing the LCD and light guide in place. The attachment fixture requires reinforcement ribs to prevent flexing under the applied pressure, and compliant cushions between the ribs and the LCD panel and between the light guide and the printed circuit board. Thus, the disclosed structure, typical of LCD panel mounting structures in common use, requires a significant number of parts, along with multiple assembly steps.
The present invention is directed to overcoming the problems described above. It is desirable to have a method for enabling automatic assembly of a LCD panel in a mobile telecommunication instrument, such as a mobile telephone. It is also desirable to have such a method that does not require additional mechanical components to fixedly mount the LCD panel in the instrument, either horizontally or in angled relationship with respect to the instrument case, and additionally is readily adaptable to vertical-assembly automatic assembly processes.
In accordance with one aspect of the present invention, a method for assembling a liquid crystal display panel in a mobile telecommunication instrument having a frame and a printed circuit board disposed in the frame, includes providing a liquid crystal display panel, providing a means for attaching the liquid crystal display panel directly to a predetermined one of the frame and the printed circuit board, and then attaching the liquid crystal display panel directly to the predetermined one of the frame and the printed circuit board.
Other features of the method for assembling a liquid crystal display panel in a mobile telephone, in accordance with the present invention, include the step of providing a means for attaching the liquid crystal display panel directly to a predetermined one of the frame and the printed circuit board by providing a tape having adhesive material deposited on both sides of the tape. Other features of the method include one side of the tape being preattached to a bottom surface of the LCD and the other side of the tape having a protective film deposited thereon, the protective film being removed from the tape prior to attaching the tape to the predetermined one of the frame and the printed circuit board. Additional features include providing a liquid crystal display panel having a flexible conductor extending from the liquid crystal display panel to a connector.
Additional features of the method for assembling a liquid crystal display panel in a mobile telecommunication instrument, wherein the frame of the mobile telecommunication instrument has a substantially planar portion and at least two support ribs extending outwardly from the planar portion and integrally formed with the frame, with each of the support ribs having a distal end that is spaced from the planar portion of the frame and adapted to support a portion of the liquid crystal display panel, includes attaching the liquid crystal display panel to the distal ends of the ribs. Other features of the method include adhesively attaching the liquid crystal display panel to the support ribs, either by an adhesive material or with a tape having adhesive material deposit on both sides of the tape. Still additional features include the distal ends of the support ribs each having a recess adapted to biasedly receive a respective portion of the liquid crystal display panel therein, and attaching of the liquid crystal display panel includes inserting portions of the liquid crystal display panel into the recesses.
Still other features of the method for assembling a liquid crystal display panel in a mobile telecommunication instrument, in accordance with the present invention, include the distal ends of the support ribs being disposed in non-parallel relationship with the substantially planar portion of the frame and the attachment of the liquid crystal display panel on the distal ends of the support ribs includes the liquid crystal display panel being disposed in non-parallel relationship with the substantially planar portion of the frame. Another feature includes the frame being the back cover of a mobile telecommunication instrument, such as a cellular telephone.
In another aspect of the present invention, a telecommunication instrument comprises a frame, a printed circuit board, and a liquid crystal display panel directly mounted to a predetermined one of the frame and the printed circuit board.
Other features of the telecommunication instrument embodying the present invention include the liquid crystal display panel being adhesively attached to the printed circuit board, such as by a tape having adhesive material disposed on both sides of the tape. Additional features include the liquid crystal display panel being adhesively mounted to the frame, such as with double-sided adhesive tape. Still additional features include the frame having a substantially planar portion and at least two support ribs extending outwardly from the planar portion. Each of the support ribs have a distal end adapted to fixedly support the liquid crystal display panel. An additional feature includes the distal ends of the support ribs being disposed in non-parallel relationship with the planar portion of the frame. Still another feature includes the distal ends of the support ribs each having a recess adapted to biasedly receive a respective portion of the liquid crystal display panel therein.
In accordance with yet another aspect of the present invention, a back cover for a telecommunication instrument has a substantially planar portion and at least two support ribs extending outwardly from the planar portion and at least two support ribs extending outwardly from the planar portion and integrally formed with the planar portion. Each of the support ribs have a distal end, spaced from the planar portion of the back cover, which is adapted to fixedly support a liquid crystal display panel thereon in oblique, or angled, relationship with the planar portion of the back cover.
Other features of the back cover for a telecommunication instrument embodying the present invention include the distal ends of the support ribs having a flat surface adapted to receive an adhesive material whereby the liquid crystal display panel is adhesively fixed to the distal respective end of the ribs. Additional features include the adhesive material being double-sided adhesive tape. Still additional features include each of the distal ends of the outwardly extending ribs having a recess provided therein that is adapted to biasedly receive a portion of the liquid crystal display panel therein.